Selvage needle motion in a narrow ware loom

ABSTRACT

A drive mechanism for the selvage knitting needle in a narrow ware loom which includes means for guiding the needle so that it always intersects an axis coincident with the fell line of the cloth and means to reciprocate the needle forwardly and rearwardly of the fell while simultaneously causing the hook of the needle to move vertically.

United States Patent [191 Kronoff et al.

[ Jan. 29, 1974 SELVAGE NEEDLE MOTION IN A NARROW WARE LOOM [75] Inventors: Clarence R. Kronoff, Worcester;

Donald F. Hayden, North Brookfield, both of Mass.

[73] Assignee: Crompton & Knowles Corporation, Worcester, Mass.

[22] Filed: June 21, 1971 [21] Appl. No.: 154,968

[52] U.S. Cl. 139/124 [51] Int. Cl D03d 47/24 [58] Field of Search 139/124 R, 124 A [56] References Cited FOREIGN PATENTS OR APPLICATIONS Germany 139/124 A Primary Examiner-Henry S. Jaudon Attorney, Agent, or FirmHoward G. Garner, Jr

[ 5 7] ABSTRACT A drive mechanism for the selvage knitting needle in a narrow ware loom which includes means for guiding the needle so that it always intersects an axis coincident with the fell line of the cloth and means to reciprocate the needle forwardly and rearwardly of the fell while simultaneously causing the hook of the needle to move vertically.

8 Claims, 6 Drawing Figures PATENTEDJAN 2 9 I974 SHEEI 2 OF 3 FIG.3

SELVAGE NEEDLE MOTION IN A NARROW WARE LOOM BACKGROUND OF THE INVENTION This invention relates to drive means for the latch knitting needle in a narrow fabric loom such as that shown in US. Pat. No. 3,102,557 to R. W. Gustavson et al. Such looms have a weft-inserting carrier for projecting successive loops of weft yarn from a stationary supply through successive warp sheds from one side of the shed and binding the loop of weft at the opposite side of the shed by knitting it through the previous weft loop or forming a knitted chain from a catch thread through the weft loops.

Many needle motions have been developed to insure that the weft loop is caught from each weft insertion. In many cases, knitting needle motions have been developed for specific purpose such as conforming to the particular motion of the weft inserter, knitting a catch thread or providing dwells at various portions of the operating cycle for variations in weaving requirements It has been recognized in the trade that in the majority of cases it is essential that the hook of the knitting needle be given a vertical motion in addition to the usual forward and rearward reciprocation to insure that the weft loop is caught by the hook of the knitting needle. Many of the known designs for moving the hook vertically have been successful, to varying degrees, for capturing the weft loop. These designs include sliding cam blocks, crank levers and various combinations thereof.

By moving the hook of the knitting needle vertically, the shank of the needle is also given vertical motion. Since there is always a loop of weft around the shank of the needle, vertical motion of the shank causes the loop to stretch. This may cause unevenness and looseness in the knitted selvage. The problem is mOre acute when light filling yarns are used, particularly those with fine filaments. When the knitting needle passes through the loop, there is considerable friction between the shank of the needle and the weft loop due to the pulling of the needle against the loop which causes the fine filaments to break. This problem can be alleviated by easing the tension of the filling yarn to allow the filling loop to stretch easily but this causes a greater looseness in the knitted selvage and an inferior fabric.

The trade has recognized some of the above problems and the more recent latch needle drives operate so that the shank of the needle has limited vertical motion at the point where it passes through the weft loop but none of these have been successful in limiting the vertical displacement of the needle shank within the weft loop to the degree necessary to alleviate all of the above problems.

SUMMARY OF THE INVENTION It is a primary object of the present invention to provide a drive for reciprocating a knitting needle wherein the hook of the needle is moved vertically and yet there is no vertical movement of the shank of the needle at the point where it passes through the weft loop.

The above object is accomplished by guiding the knitting needle so that it can be reciprocated and pivoted only at the point where it passes through the weft loop providing drive means for reciprocating the knitting needle rearwardly and forwardly to the needle while causing the knitting needle to pivot. A specific mechanism for doing this is disclosed herein which includes a guide block pivoted on an axis which is coincident with the fell line of the fabric and a support for the knitting needle which is slidably guided bythe block. The needle holder passes through said axis as it slides relative to the block and the needle is held by the holder so that it too passes through the same axis. Since the previously inserted weft loop, through which the needle passes, is located at the fell, any vertical motion imparted to the needle will cause the shank of the needle to pivot within the weft loop and thereby avoid any stretching or abrasion of the loop.

The invention will be more clearly understood from the following detailed description and the drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary plan view of a double fabric needle loom to which the invention is applied;

FIG. 2 is a section, on an enlarged scale, taken along line 2-2 in FIG. 1, looking in the direction of the arrows and showing the knitting needle in its forward position;

FIG. 3 is an enlarged plan view of the needle driving means of the present invention and showing the knitting needle for each fabric in its rearward position;

FIG. 4 is a section taken along line 4-4 of FIG. 3;

FIG. 5 illustrates a modification of the knitting needle drive; and

FIG. 6 illustrates a further modification.

DETAILED DESCRIPTION Referring to FIG. 1, the preferred embodiment of the needle drive assembly of the present invention is generally indicated at 10 and is shown applied to a double fabric needle loom indicated generally at 12. This loom includes shedding mechanism 14, beat-up means 16 and inserters 18 for inserting wefts W from an outside source of supply, through successive warp sheds. Although a double fabric loom is shown, it is to be understood that th5 invention could be applied to single fabric loom as well. When the invention is applied to a double fabric loom, it is located between the two fabrics, indicated at F, as shown in FIG. 1. The weft is inserted in the form of loops from the outer sides of both warp sheets; indicated at 20. There is a knitting needle, 22, for each fabric for binding the weft loop at the inner edge of the fabrics. This binding can be accomplished by interknitting successive weft loops with each other as shown in US. Pat. No. 3,102,557 to R. W. Gustavson et al.; by knitting a catch cord chain through the weft loops or knitting a catch cord together with the weft loops, as shown in US. Pat. No. 3,403,706 to J. D. Shackleton et al.

Referring particularly to FIGS. 2-4, needle drive assembly 10 includes a guide block 24 pivotally mounted between a pair of brackets 26. The axis about which guide block 24 pivots is inditated at 27 and is coincident with the fell 28 of both fabrics F. Assembly 10 also includes a needle holder 30 which has an elongated portion 32 extending through a hole 33 in guide block 24 in a sliding relationship therethrough. elongated portion 32 extends through axis 27 so that its longitudinal axis is perpendicular to axis 27. The knitting needles 22 are attached at opposite ends of holder 30 so that they extend close to and parallel with the inside edges of their respective fabrics F as shown in FIG. 1.

22 in the path indicated by dot and dash lines 38 in FIG. 2. The proportions of the driving elements are such that the rearward and forward dimensions of the needle path are greater than the vertical dimensions since the hooks 40 of the knitting needle need only move a relatively small distance vertically to catch the weft loop. Most of the driving time will therefore be devoted to the forward and rearward motion of the knitting needles in keeping with ever increasing loom speeds. Although the hook 40 of each knitting needle moves vertically during each reciprocation, it will also be observed in FIG. 2 that the shank of the knitting needle pivots about axis 27 which is represented by a point in FIG. 2. Since axis 27 is coincident with the fell 28 of the fabric, the knitting needle will also pivot within the previous weft loop, indicated at 42, through which it extends and thereby avoid any stretching or damaging of the weft loop. The knitting needle picks up the newly inserted weft loop as it moves from the rearward position shown in FIG. 3 and pulls it through the previous weft loop 42 as it approaches its forward position as shown in FIG. 2. Since loop 42 is at the fell, the

hook must pass forward of the axis 27 in order to pull the new weft loop therethrough. This is one reason that a portion such as 32, rather than the needle itself, has to extend through the guide 24.

Referring to FIG. 5, there is shown a modification indicated generally at 10 wherein the actuator for the needle drive comprises a lever 44 pivoted at one end to a base 46 and at its other end to an elongated portion 32' of a needle holder 30 which is identical to holder 30. Elongated portion 32' extends through a hole in a guide block 24'. Lever 44 is reciprocated along an are 48 by an eccentric 50 which in turn reciprocates the hook 40' of the knitting needle 22' along an are 52. As in the case of the preferred embodiment, needle 22' is reciprocated through and is pivoted on axis 27.

Referring to FIG. 6, there is shown a further modification indicated generally at 10". In this embodiment the knitting needle indicated at 22" is mounted in a holder 30" which is slidable in a guide block 24" pivotally mounted at axis 27. A lever 54 is pivotally mounted at its lower end to a base 56. One end ofa link 58 is pivoted to the upper end of lever 54 and the other end of link 58 is pivoted to holder 30". A block 60 is slidable within a slot 62 in lever 54. Block 60 is pivoted at 64 to a rotating drive member 66 which rotates the pivot point 64 in a circle indicated at 68. The outer portion of member 66 has a cam surface indicated generally at 70 which has a high ,8 portion 72 and a low portion 74. A spring 76 maintains guide block 24" against the cam surface 70. Drive member 66 makes one rotation for each weft insertion to reciprocate holder 30" within guide block 24". At the same time, cam surface 70 will rock guide block 24 around axis 27 so that the reciprocating motion of holder 30 and the pivoting motion of guide block 24" will cause the hook 40" of the needle to move in the path indicated by the dot and dash line 78.

We claim:

1. In a loom having means for forming a warp shed, a weft carrier for projecting successive loops of weft yarn through successive warp sheds from one side thereof to weave a fabric, a knitting needle mounted at the opposite side of the shed for forming a selvage which binds said weft loops, said knitting needle having a shank portion and a hook portion, means for driving said knitting needle comprising:

a. a needle holder for supporting said needle for reciprocation of a portion of said holder and said needle, through, and. for a pivoting motion about. a fixed axis which is substantially coincident with the fell of the fabric being woven on said loom; and

b. an actuator for reciprocating said knitting needle and said needle holder while simultaneously pivot-. ing said needle and said holder about said axis.

2. In a loom as described in claim 1 wherein said knitting needle is fixed to said needle holder and said needle holder has an elongated portion extending substantially parallel to the knitting needle.

3. In a loom as described in claim 1 wherein said actuator comprises a crank pivotally connected to said holder.

4. In a loom as described in claim I wherein said elongated portion of said needle holder extends through a guide block and said guide block is spaced from the edge of said fabric and pivotally mounted on said axis.

5. In a loom as described in claim 4 wherein said guide block has a hole which extends therethrough substantially perpendicular to and intersecting said axis and wherein said elongated portion extends through said hole in a sliding relationship with said guide block.

6. In a loom as described in claim 5 wherein said loom is equipped to weave two fabrics side by side and that said guide block and needle holder are located between said fabrics and wherein said needle holder supports a pair of knitting needles which extend to the outside of said guide block on opposite sides thereof for forming knitted selvages on the two adjacent sides of said two fabrics.

7. In a loom as described in claim 1 wherein said actuator comprises:

a. a base;

b. a lever pivotally mounted at one end to said base and pivotally connected at its other end to said needle holder; and

c. drive means for oscillating said lever and thereby reciprocating said needle holder and pivoting said guide block.

8. In a loom as described in claim 1 wherein said actuator comprises:

a. a base;

b. a lever pivotally mounted at one end to said base;

0. a link, one end of which is pivotally connected to the other end of said lever and the other end of which is pivotally connected to said needle holder;

(1. drive means for oscillating said lever and thereby reciprocating said needle holder; and

e. cam means for pivoting said guide block. 

1. In a loom having means for forming a warp shed, a weft carrier for projecting successive loops of weft yarn through successive warp sheds from one side thereof to weave a fabric, a knitting needle mounted at the opposite side of the shed for forming a selvage which binds said weft loops, said knitting needle having a shank portion and a hook portion, means for driving said knitting needle comprising: a. a needle holder for supporting said needle for reciprocation of a portion of said holder and said needle, through, and for a pivoting motion about, a fixed axis which is substantially coincident with the fell of the fabric being woven on said loom; and b. an actuator for reciprocating said knitting needle and said needle holder while simultaneously pivoting said needle and said holder about said axis.
 2. In a loom as described in claim 1 wherein said knitting needle is fixed to said needle holder and said needle holder has an elongated portion extending substantially parallel to the knitting needle.
 3. In a loom as described in claim 1 wherein said actuator comprises a crank pivotally connected to said holder.
 4. In a loom as described in claim 1 wherein said elongated portion of said needle holder extends through a guide block and said guide block is spaced from the edge of said fabric and pivotally mounted on said axis.
 5. In a loom as described in claim 4 wherein said guide block has a hole which extends therethrough substantially perpendicular to and intersecting said axis and wherein said elongated portion extends through said hole in a sliding relationship with said guide block.
 6. In a loom as described in claim 5 wherein said loom is equipped to weave two fabrics side by side and that said guide block and needle holder are located between said fabrics and wherein said needle holder supports a pair of knitting needles which extend to the outside of said guide block on opposite sides thereof for forming knitted selvages on the two adjacent sides of said two fabrics.
 7. In a loom as described in claim 1 wherein said actuator comprises: a. a base; b. a lever pivotally mounted at one end to said base and pivotally connected at its other end to said needle holder; and c. drive means for oscillating said lever and thereby reciprocating said needle holder and pivoting said guide block.
 8. In a loom as described in claim 1 wherein said actuator comprises: a. a base; b. a lever pivotally mounted at one end to said base; c. a link, one end of which is pivotally connected to the other end of said lever and the other end of which is pivotally connected to said needle holder; d. drive means for oscillating said lever and thereby reciprocating said needle holder; and e. cam means for pivoting said guide block. 